Browsing by Author "Pedrajas, Sharon Ann G."
Occurrence and histopathogenesis of a didymozoid trematode (Gonapodasmius epinepheli) in pond-reared orange-spotted grouper, Epinephelus coioides A didymozoid trematode encapsulated in the gills of orange-spotted grouper, Epinephelus coioides Hamilton, was observed in October 1997 and September 1999 among pond-reared fish in the Philippines. Capsule prevalence was 33% and 18% and mean intensity 2 and 1, respectively. The opaque-white and yellowish capsules were found only on the first gill arch and were attached lengthwise along the posterior surface of the primary gill filaments. When the capsules were opened, long thread-like worms were revealed, which were identified as Gonapodasmius epinepheli Abdul-Salam, Sreelatha and Farah. The parasites were encapsulated between the basement membrane of the epithelium and the efferent artery of the gill filament. The response of the host included mild hyperplasia of the interlamellar epithelium and an increase in the number of mucous cells.
ArticleCR Lavilla-Pitogo, HS Marcial, SAG Pedrajas, ET Quinitio & OM Millamena -
Asian Fisheries Science, 2001 - Asian Fisheries SocietyTo support studies on the development of broodstock and hatchery technology for mud crabs under the genus Scylla, the SEAFDEC Aquaculture Department maintains captive broodstock in land-based tanks. Disease problems seen in broodstock after being held for three months in these tanks include shell disease due to a combination of fouling organisms and chitinoclastic bacteria, bacterial contamination of the hemolymph, parasitic infestation on the gills and shell, and loss of appendages. Shell disease was manifested as off-white and black patches on the shell, that progressed and became perforations exposing underlying tissues. The hemolymph of a significant number of newly recruited crabs harbored mixed populations of sucrose-fermenting vibrios. Pedunculate cirripedes were found in large numbers both in the gill region and on the shell, boring through and creating perforations in the latter. Nematodes and other saprophytic organisms enter the crab through these perforations. The fouling problems that affect the integrity of the shell are considered to reduce the life span and reproductive potential of captive broodstock under tank conditions; therefore, regular cleaning of the shell is recommended to minimize shell fouling.
ArticleI Lantin-Olaguer, SA Pedrajas-Mendoza, R Pakingking & A Yamamoto -
Silliman Journal, 2010 - Silliman UniversityDetermination of the presence/absence of coliforms as the pollution indicator bacteria, total coliform count (TCC) and fecal coliform counts specifically Echerichia coli were carried out on specific sampling points in Jalaur River namely: Banban Pequeño (upstream), Calinog, Moroboro, Dingle, Passi near Sugar Central Mill and National Power Corporation (NPC) (midstream), and Nabitasan, Leganes (downstream) during the wet and dry months. Samples were analyzed using a defined technology, the Colilert® method, and its accuracy was verified with the conventional method (APHA Standard Methods). Results showed that coliforms were present in all sampling sites. In Calinog, total coliform count (TCC) was high (900 x101 MPN/100 ml) in July. Increased coliform abundance was associated with high rainfall due to animal wastes that were carried by runoffs. In September, Passi, near NPC, TCC and E. coli counts were 640 x101 and 630 x 101 MPN/100 ml, respectively. Reduction in counts in January, February and March was observed. Sediments in Passi near Sugar Central Mill during milling time in February showed a high TCC of 116 x 104 MPN/100 ml which was attributed to reduced current and disturbance, and silty loam sediments texture that favored bacterial adsorption to sediments. Dingle site exhibited a domination of other coliforms over E. coli in January and March. In Leganes, highest TCC of 551 x 101 MPN/100 ml was obtained in September. Coliform loads varied by season which was influenced by the availability of the nutrients and tolerance range to physical and chemical factors in the environment. Variability of the resultant interaction can also be attributed to climate changes such as extreme weather events—El niño phenomenon and increased nutrient loadings during heavy rains hence, increased coliform concentration in the river. The presence of coliforms in Jalaur River is indicative of contamination that can be aggravated by climate changes and implies that a potential health risk associated with pathogens causing water-borne diseases is present.